1. Field of the Invention
The present invention generally relates to a testing apparatus of integrated circuit, and more particularly to a probe card for circuit-testing.
2. Description of the Related Art
In the fabrication of the semiconductor product, integrated circuits of the wafer are tested to verify that they function appropriately and reliably. One method is to use automatic test equipment (ATE) to form a temporarily electrical connection between ATE and the integrated circuits of the wafer to verify the electrical characteristics of the integrated circuits. The probe card is used for transferring signals to the integrated circuits while testing.
Current probe card comprises a print circuit board (PCB), a substrate and a probe head. The probe head is provided with elastic probes thereon and the substrate is used to electrically connect probes and PCB. In generally, the substrate may be multi-layer organic (MLO) or multi-layer ceramic (MLC) interconnection substrate. Probes are electrically contacting via the die contact pad of the device of the wafer.
In general, in a probe card, the layout of the electrical contacts of the substrate serves as a function of transferring a fine pitch to a larger pitch. The fine pitch arrangement is usually in the probe head so as the PCB of the probe card can be made according to the larger pitch.
However, as semiconductor fabrication technology advances continue to be implemented, the pitch of the chips on the semiconductor wafer continues to shrink to the fine pitch. The demand of probe testing are faced with more challenges, such as ultra fine pitch, area array testing, high pin counts, high touchdown, and reducing cost. For instance, according to the manufacturing technology of the current MLO or MLC interconnection substrate, how to arrange more electrical contacts in a smaller space cannot match the shrink of the pitch. Hence, as the pitch is shrunk, the requirement of the technology and the cost is advanced.